The pilot who died when his small experimental plane crashed at North Perry Airport recently had replaced its engine with one from a Chevrolet Corvette, a mechanic says, a conversion the plane's manufacturer said Tuesday it frowned on.

It's not clear whether the engine swap had anything to do with Monday evening's crash that killed Douglas Pohl, 57. The practice of converting a car engine for use in aircraft is not against the law, not uncommon, and not without controversy.

Jose Obregon, a National Transportation and Safety Board investigator, said a preliminary report on the cause of the crash will be issued within a week. The agency will look at the engine, fuel systems, airworthiness, the weather and a host of other possible contributing factors.

"We look at everything," Obregon said.

Pohl was flying a Lancair IV-P built from a kit when the plane crashed shortly after takeoff around 6 p.m. He was the only one on board and no one on the ground was hurt.

Although his name has not been officially released, family members confirmed Pohl was the pilot. He lived in Jupiter and worked as a pathologist in Miramar.

Larry Cappolino, a mechanic with a company at the airport, said Pohl recently replaced the plane's engine with a motor taken from a Corvette. He said he met Pohl about a month or two ago, when Pohl was troubleshooting a fuel-delivery problem with the plane.

Timothy Ong, general manager of Oregon-based Lancair International, said automobile engines are not designed to withstand the levels needed to power even a small airplane.

"It is not something we recommend," Ong said.

Federal Aviation Administration spokeswoman Kathleen Bergen said planes with converted engines need to meet specific standards to obtain airworthiness certificates, while plane engines are certified before they're sold. The certificate for Pohl's plane listed the engine type as unknown, which Bergen said is typically an indicator that it's a converted engine.

A small airplane engine can cost two to three times that amount. The fuel to run a converted car engine is about $1 per gallon cheaper than plane fuel, and it costs less to rebuild a car engine than a plane engine, Panzera said.

Statistics were not available Tuesday on the number or percentage of plane crashes that involved converted engines.

According to the Experimental Aircraft Association, the crash rate for amateur-built aircraft is less than 1 percent higher than professionally built planes.

Panzera said people who build their planes and use car parts are also likely to take risks that might lead to accidents, but he didn't think converted engines are always to blame.

Pohl's family in Jupiter and co-workers at his office in Miramar declined to comment Tuesday.